Halsne says he talked to a military subcontractor who was present, and with the owner of the strip club, who alleged his club "routinely takes care of high-ranking employees of the U.S. embassy in San Salvador as well as visiting FBI and DEA agents."

Halsne alleges some of the agents paid female strippers inside the club for sexual favors and urged them to join them in hotel rooms.

The Secret Service told NPR's Tamara Keith that allegation "assessed as credible will be followed up on in an appropriate manner."

The Department of Defense told NPR's Larry Abramson that there are no indications that any military personnel violated any protocols for appropriate behavior, but U.S. Southern Command continues to investigate charges stemming from the Cartagena incident.

The allegation about Secret Service misbehavior in El Salvador last year is similar to this month's incident in Colombia, which came to light when a prostitute allegedly demanded more payment from a Secret Service agent. Twelve agents have been dealt with in the past two weeks, and 12 members of the military are accused of participation, according to AP.

As Mark wrote earlier, some of the Secret Service personnel said privately similar behavior occurred on other official trips. During her testimony yesterday, Napalitano said investigators had searched Secret Service records for the past 2 1/2 years and found no reports of misbehavior; they're examining older records. However, the alleged incident in El Salvador falls within the 2 1/2 year time frame.

Update at 1:13 p.m. ET. Statements From The U.S.:

We've updated the post above to reflect reaction the United States. Here's the full statement sent to NPR's Tamara Keith by Secret Service spokesman Max Milien:

"The recent investigation in Cartagena has generated several news stories that contain allegations by mostly unnamed sources. Any information that is brought to our attention that can be assessed as credible will be followed up on in an appropriate manner."

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